diff --git a/headroom/proxy/loop_callback_failure_policy.py b/headroom/proxy/loop_callback_failure_policy.py
new file mode 100644
index 000000000..a802991e3
--- /dev/null
+++ b/headroom/proxy/loop_callback_failure_policy.py
@@ -0,0 +1,20 @@
+"""Classification policy for event-loop callback failures."""
+
+from __future__ import annotations
+
+from typing import Any
+
+KNOWN_WEBSOCKET_CALLBACK_MESSAGE = (
+    "Exception in callback Connection.connection_lost(ConnectionResetError())"
+)
+KNOWN_WEBSOCKET_CALLBACK_EXCEPTION = "'ClientConnection' object has no attribute 'recv_messages'"
+
+
+def is_known_websocket_callback_failure(context: dict[str, Any]) -> bool:
+    """Return True iff this exact websockets callback failure shape is observed."""
+    if context.get("message") != KNOWN_WEBSOCKET_CALLBACK_MESSAGE:
+        return False
+    exception = context.get("exception")
+    return isinstance(exception, AttributeError) and str(exception) == (
+        KNOWN_WEBSOCKET_CALLBACK_EXCEPTION
+    )
diff --git a/headroom/proxy/server.py b/headroom/proxy/server.py
index d173e43bb..ce7e8a163 100644
--- a/headroom/proxy/server.py
+++ b/headroom/proxy/server.py
@@ -140,6 +140,7 @@ from headroom.proxy.helpers import (
     jitter_delay_ms,
     retry_after_ms,
 )
+from headroom.proxy.loop_callback_failure_policy import is_known_websocket_callback_failure
 from headroom.proxy.loopback_guard import is_loopback_host
 from headroom.proxy.memory_handler import MemoryConfig, MemoryHandler
 
@@ -2007,18 +2008,7 @@ def _request_is_loopback(request: Request) -> bool:
     return is_loopback_host(client_host) and is_loopback_host_header(host_header)
 
 
-def _is_known_websocket_callback_failure(context: dict[str, Any]) -> bool:
-    """Return True iff this exact websockets callback failure shape is observed."""
-    if (
-        context.get("message")
-        != "Exception in callback Connection.connection_lost(ConnectionResetError())"
-    ):
-        return False
-    exception = context.get("exception")
-    return (
-        isinstance(exception, AttributeError)
-        and str(exception) == "'ClientConnection' object has no attribute 'recv_messages'"
-    )
+_is_known_websocket_callback_failure = is_known_websocket_callback_failure
 
 
 _tool_schema_saved_from_tags = tool_schema_saved_from_tags
diff --git a/tests/test_loop_callback_failure_policy.py b/tests/test_loop_callback_failure_policy.py
new file mode 100644
index 000000000..f82f4a371
--- /dev/null
+++ b/tests/test_loop_callback_failure_policy.py
@@ -0,0 +1,40 @@
+from __future__ import annotations
+
+from headroom.proxy.loop_callback_failure_policy import (
+    KNOWN_WEBSOCKET_CALLBACK_EXCEPTION,
+    KNOWN_WEBSOCKET_CALLBACK_MESSAGE,
+    is_known_websocket_callback_failure,
+)
+
+
+def test_known_websocket_callback_failure_matches_exact_shape() -> None:
+    assert is_known_websocket_callback_failure(
+        {
+            "message": KNOWN_WEBSOCKET_CALLBACK_MESSAGE,
+            "exception": AttributeError(KNOWN_WEBSOCKET_CALLBACK_EXCEPTION),
+        }
+    )
+
+
+def test_known_websocket_callback_failure_rejects_other_message() -> None:
+    assert not is_known_websocket_callback_failure(
+        {
+            "message": "Exception in callback something_else",
+            "exception": AttributeError(KNOWN_WEBSOCKET_CALLBACK_EXCEPTION),
+        }
+    )
+
+
+def test_known_websocket_callback_failure_rejects_other_exception() -> None:
+    assert not is_known_websocket_callback_failure(
+        {
+            "message": KNOWN_WEBSOCKET_CALLBACK_MESSAGE,
+            "exception": AttributeError("different attribute"),
+        }
+    )
+    assert not is_known_websocket_callback_failure(
+        {
+            "message": KNOWN_WEBSOCKET_CALLBACK_MESSAGE,
+            "exception": RuntimeError(KNOWN_WEBSOCKET_CALLBACK_EXCEPTION),
+        }
+    )